Exomoons may be home to alien life, contain water, say researchers

Because of their size and distance from Earth, exomoons are very difficult to detect

Moons orbiting planets outside our solar system may contain liquid water necessary for extra-terrestrial life, according to a study.

Exoplanets are planets outside our solar system and nearly 4,000 have been discovered till now, said researchers at the University of Lincoln in the UK.

Only a small proportion of these are likely to be able to sustain life, existing in what is known as the habitable zone.

However, some planets, especially large gas giants, may harbour moons which contain liquid water.

"These moons can be internally heated by the gravitational pull of the planet they orbit, which can lead to them having liquid water